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Lexmark MX431

Lexmark MX431

etherFAX Support FAQS

What is etherFax?

By eliminating the need for costly components of a fax server, fax board, media gateways, and recurring telephony costs, the etherFAX company’s namesake solution leverages the Internet to manage all business-critical fax communications.

With etherFAX, expensive fax hardware, complex fault tolerance designs, and costly disaster recovery solutions are no longer needed. Additionally, etherFAX eliminates the complexities and costs of provisioning SIP, T.38, PRI, T1, and/or analog connections. By simply connecting on-premise fax server infrastructure to etherFAX, all fax communications are securely delivered via the cloud.

etherFAX is the fax board in the cloud, capable of processing billions of faxes each month.


Some Lexmark devices can send and receive faxes through the etherFAX service. This integration is such that an end user will not know the difference between using etherFAX or using the analog modem, except that their faxes may go through at a much faster speed (using HTTPS). The Fax Transport is set to etherFAX instead of Analog (or T.38 or G.711 for FoIP).

Note:  The Lexmark technical support agent (TSC) can also check the Fax setting from the SE setting page as shown in the following image.


My Lexmark device is displaying a "No analog phone line connected to modem, fax is disabled" error message on the panel, refer to KB Article SO9066.

  • My Lexmark device's Fax Transport is setup as etherFAX. The device has already been registered to the etherFAX portal and has been configured to connect to the etherFAX server. However, I sometimes see the "Lost connection to HTTPS Fax Server" message in the panel. The message usually clears on its own without me doing anything. What's going on with my device?
    • When a device's Fax Transport is setup as etherFAX, it needs to be connected to the etherFAX server all the time. It is highly recommended that the device be connected to a stable network connection. Any network connection problem will result into the device being unable to contact the server. When this happens, the device will post the Lost connection to HTTPS Fax Server" message in the panel. When the network problem is resolved and the device is able to contact the server again, the message in the panel will be cleared. Sometimes, it may take a while for the device to re-establish connection to the etherFAX server after the network becomes online again. To force the device to reconnect, you can reboot the device. It will try to reconnect at bootup.
  • My Lexmark device is setup to use the etherFAX transport. When I send a fax job, the call duration varies. Sometimes, the calls are short (a few seconds). Sometimes, the calls are longer (a few minutes). What's going on with my device?
    • When a device is setup to use the etherFAX transport, it connects to the etherFAX server to send and receive calls. The etherFAX server routes calls via the Secure Exchange Network (SEN) or the Public Switched Telephone Network (PSTN). There are 2 types of fax calls that may happen: 1) SEN to SEN calls 2) SEN to PSTN calls. When a phone number is dialed, the device routes the call to the etherFAX server. The server tries to determine where the destination is. If the server determines that the phone number is an endpoint within the SEN only, a SEN to SEN call is made and the fax document is transmitted using IP network speeds (fast). If the server determines that the phone number is a destination that is not within the SEN, it makes an outside call to the PSTN and the fax document is transmitted using fax speeds (slow) while the Lexmark device is made to wait for the status of the PSTN call. So if the call is routed w ithin the SEN only, the call will be short. If the call was routed to the PSTN, it will be longer like any normal analog fax call.
  • My Lexmark device is setup to use the etherFAX transport. My network connection can sometimes become unstable. During this downtime, I'm concerned that I will miss some incoming fax calls. What do I need to do to address my concern?
    • It is highly recommended to connect the device to a stable network connection for etherFAX transport to work seamlessly. However in rare cases when the network is down, you will not miss any of your incoming fax calls. Unlike a regular phone number, the phone number provided by etherFAX will never be busy as the etherFAX server is the one who is answering all incoming calls. When a fax job is sent to a phone number within the SEN (Secure Exchange Network), the job is first received by the etherFAX server and stored in the receiver's inbox within the server. The etherFAX server would then inform the receiving device that a job is available in it's inbox. The receiver would then pull the job from the server; thus clearing the job from the inbox. In the event that the receiving device is down for whatever reason, the etherFAX server will just keep the fax job in the receiver's inbox until such time that the receiving de vice becomes online again.
  • My Lexmark device is a non-harddisk model. It is setup to use the etherFAX transport. I tried to send a large fax job by scanning via ADF but I encountered a "Fax memory full" error. What do I need to do in order to send a large fax without error in my device.
    • Non-harddisk models have low fax storage memory. These models can't hold large fax jobs. However, it is sometimes still possible to send large fax jobs in these models using fax streaming mode. To use fax streaming mode, the original document is fed to the ADF when starting the fax workflow. When in fax streaming mode, the device will start the fax call and transmit fax pages while also still scanning the remaining pages via the ADF. For SEN to SEN calls, fax streaming mode is possible. For SEN to PSTN calls, the device is basically asking the etherFAX server to make the outside call to the PSTN. For this call to work, the etherFAX server needs to have the entire job at hand. Thus, fax streaming mode is not possible for SEN to PSTN calls. In order to send large documents via SEN to PSTN calls, we suggest you breakup the large document into smaller ones and send those smaller documents one at a time.
  • My Lexmark device is setup to use the etherFAX transport. Recently, it's system card has been replaced. Now, I get a "Lost connection to HTTPS Fax Server" message in the panel.
    • Whenever a Lexmark device registers to the etherFAX server, it creates an authentication token and stores it in non-volatile memory in the system card. This authentication token is used by the Lexmark device every time it connects to the etherFAX server. When the device's system card is replaced, this authentication token is effectively lost. The next time the device connects to the etherFAX server, it will attempt to register. However, the server will block the registration since the device is already marked as registered in the server's registry. A "Lost connection to HTTPS Fax Server" message is then posted in the MFP. In normal cases, the device's serial number remains the same after a system card replacement. Assuming that the device's serial number is retained with the new system card, you need to go to your etherFAX portal account and unregister the device from the etherFAX registry. Once this is don e, the Lexmark device needs to be rebooted. When it boots up, it will try to register back to the etherFAX server. The server will no longer block the registration because the device is not yet marked as registered in its registry. In very rare instances that the device's serial number has been changed after the system card replacement, the device has to be added to the etherFAX portal as a new device using the new serial number.


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